2.5 GB NICs performing at different speeds

[Harleyfart01]

Greetings! New to this board. Just realized a problem on NAS I've had for a while.
NAS = 6604T
Q2 - 2.5 GBe Ethernet ports.
Adapter #1 connected correctly at 2.5 GB.
Adapter #2 performing at 100 MB.
Both connected to Sodola 2.5GB & get same 100 MB data speed from Adapter #2 regardless of switch port utilized.
CAT6 cables have been checked. No issues.
Does anyone have any ideas?

[snapshot]

Does the second port still connect at 100Mb/s if the first port is not connected?

And what do you expect to achieve by having both NICs plugged in to the switch? How do you have them configured?